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X-CSE-ConnectionGUID: fCEe3JI2RPKORTBhvdLSwg== X-CSE-MsgGUID: 9Cf/Wl4wRxW2EFsVMeDnBg== X-IronPort-AV: E=McAfee;i="6800,10657,11864"; a="86121611" X-IronPort-AV: E=Sophos;i="6.25,203,1779174000"; d="scan'208";a="86121611" Received: from fmviesa005.fm.intel.com ([10.60.135.145]) by orvoesa112.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 03 Aug 2026 19:11:25 -0700 X-CSE-ConnectionGUID: KUMwzY9FTRiSU0SR1Bn47g== X-CSE-MsgGUID: U8Dg8g26SGOUT5Pc2eda4A== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.25,203,1779174000"; d="scan'208";a="266494953" Received: from fuxiaogu-mobl1.ccr.corp.intel.com (HELO [10.238.208.47]) ([10.238.208.47]) by fmviesa005-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 03 Aug 2026 19:11:07 -0700 Message-ID: Date: Tue, 4 Aug 2026 10:11:05 +0800 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v9 07/41] KVM: guest_memfd: Wire up core private/shared attribute interfaces To: Sean Christopherson Cc: Ackerley Tng , aik@amd.com, andrew.jones@linux.dev, binbin.wu@linux.intel.com, brauner@kernel.org, chao.p.peng@linux.intel.com, david@kernel.org, jmattson@google.com, jthoughton@google.com, michael.roth@amd.com, oupton@kernel.org, pankaj.gupta@amd.com, qperret@google.com, rick.p.edgecombe@intel.com, rientjes@google.com, shivankg@amd.com, steven.price@arm.com, tabba@google.com, willy@infradead.org, wyihan@google.com, yan.y.zhao@intel.com, forkloop@google.com, pratyush@kernel.org, suzuki.poulose@arm.com, aneesh.kumar@kernel.org, liam@infradead.org, Paolo Bonzini , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Steven Rostedt , Masami Hiramatsu , Mathieu Desnoyers , Jonathan Corbet , Shuah Khan , Shuah Khan , Vishal Annapurve , Andrew Morton , Chris Li , Kairui Song , Kemeng Shi , Nhat Pham , Barry Song , Axel Rasmussen , Yuanchu Xie , Wei Xu , Youngjun Park , Qi Zheng , Shakeel Butt , Kiryl Shutsemau , Baoquan He , Jason Gunthorpe , John Hubbard , Peter Xu , Vlastimil Babka , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-mm@kvack.org, linux-coco@lists.linux.dev References: <20260728-gmem-inplace-conversion-v9-0-35f9aec2aed2@google.com> <20260728-gmem-inplace-conversion-v9-7-35f9aec2aed2@google.com> <60d19013-d6d7-4eec-827a-2622e22cec98@intel.com> <25ab36cf-888a-4547-b3f7-5bd4e057c1d0@intel.com> Content-Language: en-US From: Xiaoyao Li In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Stat-Signature: h55qbfzy4jgpp19dsfscr36c1a8csucg X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: D870818000A X-Rspam-User: X-HE-Tag: 1785809485-376916 X-HE-Meta: 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 eAqxen2+ /bO5xV0xbNUmvIzkm2wf+UrGxIL33aUfrUaeDo8eqG/40pvscvtOHPdXzrqR2tIPknlnY+682lTGPUJfIN3TQjl7zvucVFDqFcBQjIReXZfqwK8DVvdkP6AlYo/XRW2aoquzscpyrNj5l8t6ST3R/BZuicevxa/kacw7WTog0iwLI4TZKPmr1zesBY2jEcwNvkSeX7JXYKzFMUuFxXzAW1YAfYlz1MiDdaK+cmrlWsxIp7cfy5+6MW+/iZw== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 8/3/2026 11:33 PM, Sean Christopherson wrote: > On Mon, Aug 03, 2026, Xiaoyao Li wrote: >> On 8/1/2026 12:26 AM, Sean Christopherson wrote: >>> On Fri, Jul 31, 2026, Xiaoyao Li wrote: >>>> On 7/31/2026 4:42 AM, Ackerley Tng wrote: >>>> If kvm_range_is_private() is useful/required by huge page support, then let >>>> the huge page series to introduce it. It has nothing to do with the in-place >>>> conversion series. >>> >>> If it weren't for the fact that the range-based search is used later in this >>> series, I would 100% agree with Xiaoyao. >>> But since the core logic is used and needed elsewhere, >> >> I don't see it a problem. Without introducing kvm_range_is_private() in this >> patch, the core logic of range-based search on gmem can still be introduced >> as kvm_gmem_range_has_attributes() directly in patch 10 or in a separate >> patch. >> >>> and because kvm_range_has_vm_memory_attributes() takes a range, my vote is >>> to provide the plumbing now, even though a small portion of it isn't >>> strictly necessary. >> >> So my initial feedback was "we can just use kvm_mem_is_private(kvm, gfn)". >> It makes code simpler. > > My apologies, I hadn't actually applied v9 to look at the full context. I agree, > providing kvm_range_is_private() is completely unnecessary. It's not even really > a problem with this patch, it's a pre-existing issue that can and should be > addressed with a prep patch. yea, that's why I said "it seems can be a separate patch. " >> And as a bonus, the logic to choose between gmem-based attribute query and >> vm-based attribute query is hidden from the static call. > > I don't follow. What do you mean by "hidden from the static call?" The whole > point of using a static call is to select between gmem-based and vm-based private > memory. Or are you saying the populate() flow doesn't need to manually check > gmem_in_place_conversion? yea. By using kvm_mem_is_private(), we don't need the kvm_range_is_private() introduced by this patch, which has the gmem_in_place_conversion check. >> The second bonus of dropping kvm_range_is_private() is that we can eliminate >> one more chunk in patch 20. > > Ya. > > Untested, but unless I'm missing something, patches 6 and 7 of this series can > be replaced with the attached patches (6 and 7 should be squashed together no > matter what). The attached patches are just what I wanted. They look good!